Railway traffic controlling apparatus



Oct. 12, 1965 R. J. BUSH 3,211,017

RAILWAY TRAFFIC CONTROLLING APPARATUS Filed Sept. 21. 1960 5 Sheets-Sheet 1 I INVENTOR. Rankin J Bus]:

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HIS A TTORZVEY Oct. 12, 1965 J BUSH RAILWAY TRAFFIC CONTROLLING APPARATUS Filed Sept. 21. 1960 5 Sheets-Sheet 2 wfi SN 3% m NN @Q MMN MN Oct. 12, 1965 R. J. BUSH 3,211,017

RAILWAY TRAFFIC CONTROLLING APPARATUS Filed Sept. 21, 1960 Sheets-Sheet 3 1! 0 15.? 1.?7 2 13? 1 54 m /////7/////// -////////////VA/// ////J//V//L/ 159 M159 \\159 1255i O Insulazian 176 136 a 7 .5 150 .50 146 145 44146 5 124 Insalmiazz 44a 4 Km 14 3/ INVENTOR. Rankin J Bush HIS ATTORNEY Oct. 12, 1965 R. J. BUSH 3,211,017

RAILWAY TRAFFIC CONTROLLING APPARATUS Filed Sept. 21. 1960 Sheets-Sheet 5 65674779 90 .56 6162 B 54 764, 164a 106 65a 104: 164 as 97 j? I 100 571 55 (/l //J 59 4646 a Q5" fiza 1a Ash/6a} 5a 62 m2 m6 EM 104 F 6 a2 99 65 56 16415 92 \\\\\\\\EEJ\J\\\(\1 v I 65 67 66'- 69 71 Z3. 0 74 91 56 I I\ \\\\\\\\\\\\\\\Q 2 Fig. Z

INVENTOR. Rankin Jf Bush HIS ATTORNEY United States Patent 3,211,017 RAILWAY TRAFFIC CONTROLLING APPARATUS Rankin J. Bush, Jeannette, Pa., assignor to Westinghouse Air Brake Company, Wilmerding, Pa., a corporation of Pennsylvania Filed Sept. 21, 1960, Ser, No. 57,538 7 Claims. (Cl. 74-472) My invention relates to railway traffic con-trolling apparatus, and particularly to apparatus of the type comprising a train stop device located in the trackway and provided with a trip arm arranged to cooperate with brake governing means carried on the train.

Train stop devices of this type are normally operated in conjunction with the usual traffic controlling signals employed in signaling systems and provide emergency control over the movements of trains, in the event an engineer fails to observe or heed such signals, by releasing the trip arm from an ineffective position out of the path of the train-carried governing means to a position effective to actuate the train-carried governing means and thereby cause an automatic application of the brakes.

Accordingly, an object of my invent-ion is to provide an improved form of train stop device of the type described which is capable of rapid-1y moving the trip arm between effective and ineffective positions, and which may be economically and readily installed.

In railroad systems, a source of electric current is normally readily available at any point throughout the systern.

It is therefore a specific object of my invention to provide a train stop device in which the elements effective for lowering the trip arm and for subsequently holding it in the lowered position are operated entirely by electric current.

A more general object of my invention is to provide an improved train stop device which is rugged and sturdy in construction, and which is thoroughly reliable and efficient in operation.

Other objects and characteristic features of my invention will become apparent as the specification proceeds.

In the attainment of the foregoing objects, I provide a train stop device including a trackway trip arm operated to an ineffective position and biased by spring means toward an effective position. Three planetary gears carried by a shaft operatively connected with the trip arm is interposed between an internal gear and a sun gear, the sun gear being arranged to be held against rotation by an electromagnetic brake whenever the brake is energized. A motor is connected with a nonreversible worm drive, the worm gear of which is held in driving relation with the internal gear by means of a slip coupling. T-o lower the arm, the motor and brake are energized concurrently and the planetary gear is revolvably driven about the sun gear by the internal gear to rock the shaft through an angle suflicient to swing the trip arm out of the path of the traincarried brake actuating means. Circuit means responsive to movement of the trip arm open the circuit through the motor when the trip arm reaches an ineffective position. The brake, however, is retained energized and continues to prevent thesun gear from revolving to retain the trip arm in the posit-ion to which it has been operated. If, now, it is desired to return the trip arm to an effective position, external circuit means which operate in conjunction with wayside signals open the brake circuit to release the sun gear and thereby allow it to revolve freely on its axis under the action of the planetary gear and spring biasing means.

I will describe one form of train stop device embodying my invention, and will then point out the novel features thereof in the appended claims.

In the accompanying drawings, FIG. 1 is a plan view of ice the device embodying my invention illustrating the rela tive positions of the parts with respect to a track rail.

FIG. 2 is a side view of the device shown in FIG. 1.

FIG. 3 is a top plan view of the train stop device shown in FIG. 1, with the covers of various compartments removed.

FIG. 4 is a view partly in elevation and partly in section taken on line IV-IV of FIG. 3.

FIG. 5 is a longitudinal sectional view taken substantially on line VV of FIG. 3.

FIG. 6 is a fragmentary sectional view taken substantially on line VIV I of FIG. 3.

FIG. 7 is a fragmentary sectional View taken substantially on line V'IIV I I of FIG. 3.

FIG. 8 is an enlarged fragmentary view of the segment gear included in the device embodying my invent-ion.

FIG. '9 is a fragmentary view taken substantially on line IX-IX of FIG. 3, showing the contact fingers in the motor circuit of the train stop device of my invention.

FIG. 10 is a schematic diagram showing one form of electrical circuit for controlling the device of FIG. 1.

Similar reference characters refer to similar parts in each of the several views.

Referring to the drawings, and particularly to FIGS. 1 and 12, there is shown a train stop device over which traffic moves in the direction of the arrow and which comprises a housing 10 mounted on the ties 12 of the trackway adjacent one of the rails 13. A shaft 14 (see FIG. 5) of square shape is journaled in bearings, presently to be described, in housing 10. Shaft 14 extends outwardly from the housing and is connected with one end of an extension shaft 16 by means of a coupling generally indicated 17. The other end of shaft 16 is journaled in a bearing bracket 18 mounted on ties 12 on the outer side of rail 13. A track trip arm 20 is secured to shaft 16 adjacent the rail 13 over which traffic is to be controlled by the trip arm, and is adapted to be swung by mechanism, presently to be described, between a substantial-1y horizontal inoperative position and a substantially vertical effective position in which it is illustrated in the drawings, and in which it lies in the path of, and may set in operation, suitable train-carried governing means, such, for example, as the lever of a valve in the air line controlling the application of the brakes. A stop 22 for the trip arm 20 is provided with an element 22a made preferably of resilient material, and is mounted on the bracket 18.

Referring now to FIGS. 4 and 5, a segment gear 24, on *whose upper portion gear teeth are formed, is journaled in a thin wall bearing 26 (FIG. 5) pressed or otherwise firmly fixed between the housing and an extending portion 24a of the segment gear. Portion 24a of segment gear 24 is provided with a substantially square hole 24b through which the shaft 14 projects in close fitting relation, whereby shaft 14 is constrained to rotate with the segment gear. A second bearing 30 for shaft 14 is fixed thereto by means of a pin 32, and this hearing is formed with a collar 30a and provided with a substantially square hole 30b through which the other end of shaft 14 projects. A tube-like member 34, whose purpose will presently be made clear, extends through an opening formed in housing 10 and is journaled on bearing 30. Member 34 is provided with inner faces which abut against the collar 30a of bearing 30 and against the outside wall of housing 10 and this member is attached to the housing by means of screws 36 (FIG. 3). Shaft 14 is prevented from moving longitudinally toward the right, as oriented in FIG. 5, by means of a collar 38 whose inner end abuts against member 34.

Shaft 14 is biased in a clockwise direction, as viewed in FIG. 4, in order to urge the trip arm 20 to an upright operative position, by means of a pair of identical springs 40 and 41. These springs surround a spring cage 42 arranged in axial alignment with shaft 14, and are compressed between member 34 and a circular plate 44 which may be connected with gear 24 in any suitable manner but which, as herein shown, is connected by suitable rivets 45 peened at one end and provided at the other end with large diameter portions snugly received by holes in gear 24. As seen in FIG. 5, shaft 14 extends through plate 44 with considerable clearance. The inner end of each spring is Wound about a transverse lug 44a (FIG. 4) formed on plate 44 and its other end projects into a spring retaining hole 340 (FIG. 5), formed in member 34. Compression is applied to springs 40 and 41 by locking segment gear 24 against rotation, in a manner presently to be described, and rotating member 34 relative to bearing 30 prior to attaching it to housing by the aforementioned screws 36. In the preferred embodiment of my invention, a number of threaded holes for receiving the screws 36 may be provided in housing 10, these holes preferably being spaced by any suitable angular distance which will permit springs 40 and 41 to be initially adjusted to variable degrees of compression. It will be understood, moreover, that the pressure exerted by these springs at all times tends to hold the parts in the positions shown in FIGS. 1 and 2, that is, with trip arm occupying an upright or operative position. It is apparent that it is necessary to overcome the pressure of springs 40 and 41 in order to swing arm 20 to an inoperative position to permit the passage of a train over the trackway without interference. Also, if desired, a single one of springs 40 and 41 may be employed but, as is apparent, the use of two springs as illustrated insures the return of the trip arm to the operative position in the event one of the springs becomes defective.

Segment gear 24 meshes with a relatively small gear or pinion 46, FIGS. 4 and 6, which is keyed to one end of a countershaft 48 and affixed thereto by means of a nut 50. Counte-rshaft 48 extends through and is journaled in a main bearing sleeve 52 set in housing 10. Integrally formed on, or otherwise suitably secured to, countershaft 48 is a spider 54 upon the arms of which are journaled planetary gears 56, by means of journal pins 58 which pass through the planetary gears 56 and the extremities of the arms of the spider 54. Surrounding these planetary gears 56 and meshing therewith, is an internal gear 60 supported by means of a gear carrier 61 having a screw-threaded portion 61a journaled on the periphery of sleeve 52 so that gear carrier 61 and countershaft 48 are free to rotate relative to each other. Internal gear 60 is secured to the arms of the gear carrier by means of screws 62. Portion 61a of the gear carrier is interposed between a face 10a of the housing and a retaining ring 63 mounted on sleeve 52 and, therefore, is prevented from moving axially on the sleeve. A worm gear 64 is mounted on portion 61a of gear carrier .61 and meshes with a worm 66 pinned to a shaft 67 journaled in bearings 68 and 69 (FIG. 7). Shaft 67 is connected, as by a coupling 70, with the shaft 72 of a motor 73. A support 71 for bearing 69 projects into an opening in housing 10 and is secured by screws 74 to the housing. The compartment which houses the gears is preferably provided with an oil bath indicated in the conventional manner, and is also provided with a removable cover-76.

Worm gear 64 is interposed between gear carrier 61 and a slip coupling Q which includes a generally cylindrical body 78 concentrically mounted on gear carrier 61 and connected therewith as by a key 79, which key effects their simultaneous rotation. The body 78 is provided with a plurality of holes 80, only one being shown, extending parallel to the axis thereof and spaced from each other by a suitable angular distance. Disposed in the holes 80 and urged into firm pressure contact with body 78 by a disk 83 mounted on the periphery of portion 61a of the gear carrier, are compressed springs 82 which, through the medium of body 78, bias worm gear 64 into frictional driving engagement with gear carrier 61 to transfer the worm gear torque to the internal gear. Axial movement of disk 83 away from the springs is prevented by a nut 84 threadably connected with portion 61a of the gear carrier. To prevent rotation of disk 83 relative to gear carrier 61, I provide on disk 83 and toward the center thereof a tab 83a snugly seated within the keyway in gear carrier 61 provided for the key 79. It will readily be understood that by varying the position of nut 84, the compression of springs 82 may be varied, thus permitting the torque which slip coupling Q will transmit to be varied. The compression of springs 82 will usually be so adjusted that the slip coupling will not slip as long as the load on worm gear 64 is within the normal working load of motor 73, but that, as soon as the load on the worm gear exceeds the normal working load of the motor, the slip coupling will slip and allow relatively unrestrained rotation of the worm gear alone on the journaled portion of gear carrier 61. Following adjustment of nut 84, the nut may be locked from rotating in a reverse direction by any suitable manner but, as herein shown, it is locked by overlapping a segment of disk 83 firmly against the periphery of nut 84. Moreover, in my present invention, the 'worm and worm gear are made self-locking or nonreversible, that is, the worm is so proportioned that while it will drive the worm gear, the worm gear cannot drive the Worm. The reason for the self-locking worm drive will be discussed in detail hereinbelow.

The train stop device also comprises an electromagnetic brake B (FIG. 6), whose parts are supported by and enclosed in a frame 85 in turn attached to and projecting into an opening provided in housing 10. The brake includes a winding 86 mounted on a core 87 provided with radially spaced annular pole pieces 87a and 87b separated by an insulative brake shoe ring 106. Core 87 is mounted, in turn, on a cover plate attached to frame 85 by screws 97. A brake shaft 88 is journaled in a bearing 89 and, by means of a pin 90, carries on the end thereof adjacent the gear carrier a sun gear 91 in mesh with the planetary gears. A hub 92 is keyed to the other end of shaft 88 and is made fast thereto by means of a washer 93 and nut 94 A magnetizable armature 96 is splined to hub 92 so that it is free to slide a limited distance along the hub but is constrained to rotate with it. Armature 96 is disposed out of contact with pole pieces 87a and 87b when winding 86 is deenergized, as herein shown, but is arranged to engage the pole pieces when winding 86 becomes energized to accordingly prevent shaft 88, and, consequently, sun gear 91 from rotating. An oil seal 100 surrounds the brake shaft to minimize oil seepage into the brake compartment. If, however, oil seepage does occur, it is desirable that the oil be prevented from affecting the operation of the brake. To this end, an oil throw-off plate 102 is provided and is held firmly by hub 92 against a shoulder 88a on shaft 88 and thereby rotates with the shaft. With this arrangement, any lubricant which collects on plate 102 will be thrown against the inner walls of frame 85 as plate 102 rotates, and will accumulate in a sump at the base of frame 85 provided with a drain plug 104.

The device also embodies a circuit controller for establishing certain electric circuits according to the position occupied by the trackway trip arm. This controller is contained in a chamber 108 formed in the housing 10 (FIGS. 3, 4 and 5), and to which access may be conveniently had through a removable cover 110. Located within chamber 108 and mounted at one end by means of screws 112 on lugs 114 (see FIG. 5), and at the other end mounted by means of similar screws 116 on a thin plate 118 secured to other lugs 119, by means of screws 120, is a substantially H-shaped contact support 122 of suitable insulating material. Two sets of electrical contact fingers 123a and 123k arranged in spaced parallel relation are mounted on the support 122 on opposite sides thereof and are adapted to cooperate with two sets of underlying contact fingers 124a and 1241: (FIG. 4) also mounted on support 122. Also included in the contact arrangement of my invention and illustrated in FIG. 3, but being best illustrated in FIG. 9, is an electrical contact which, as will appear, may be used for controlling the energization of motor 73, which contact comprises two contact fingers 125 and 125a mounted on support 122 and, as herein shown, engaging one another for closing the circuit through motor 73. A block 126 of insulating material (see FIGS. 4 and 5) is held against the underside of support 122 by means of a nut 127 threaded on a screw 128 which extends downwardly through support 122, block 126, and one end of a contact finger 130 whose free end cooperates with one of the contact fingers 124a to form a normally closed back contact 124a-130. It will become apparent as the specification proceeds that the contact 124a-130 may be used for controlling an electrical check circuit of the type well known in the art which checks the operation of certain parts, presently to be described, of the train trip device.

It will be appreciated that during maintenance or inspection of the device embodying my invention, it is desirable to interrupt the energizing circuits for motor 73 and brake B, in order to prevent temporarily their operation and thereby insure the safety of personnel servicing the device. To this end, I provide a safety switch which may be connected in the energizing circuits of the motor and brake. This switch comprises a bracket 132 (FIGS. 3, 4 and 5) mounted on support 122 as by upwardly extending screws 133 engaged by nuts 137, and further comprises a pin 134 on which a lever 135 is pivotally mounted. Lever 135 is designed to cooperate with a push block 110a (FIG. 4) on cover 110 so that when the cover is closed block 110a will engage lever 135 and force it downwardly into engagement with a contact finger 136 which, in turn, engages a cooperating contact finger 138. This contact 136-138 will, of course, be connected in the circuits for energizing motor 73 and brake B, as will appear. At times, therefore, when cover 110 is removed or open, contact finger 136 will act upon lever 135 and cause it to revolve in the opposite direction an extent sufficient to enable contact finger 136 to become disengaged from contact finger 138. Contact fingers 136 and 138 are similarly mounted on support 122 and, as shown herein, each of the contact fingers mounted on support 122 is provided with a terminal post 139. Moreover, the terminal post for contact finger 130, as seen in FIG. 4, extends through an opening in block 126 and thus prevents this block from turning relative to support 122.

The contact fingers 124m of the one set are moved into engagement with their associated contact fingers, and the contact fingers 124b of the other set are flexed out of engagement with their associated contact fingers, simultaneously with changing the disposition of back contact 124a-130 and motor contact 125-125a, by means of a rocker 140 having essentially a quadrangular shape. Rocker 140 is pivotally mounted, midway between its ends, on a pair of shafts 141 and 142 disposed in axial alignment with each other and connected with the housing 10. The shorter sides of rocker 140 are provided with plates 144 of insulating material held firmly on the rocker by means of nuts 145 threaded on screws 146. Screws 146 extend through plates 144 and through relatively thin strips 148, of insulating material, whose upper ends project above and are bent downwardly against the upper surface of the rocker in order to prevent electrical creepage between the rocker and a plurality of contact actuating screws 150 adjustably mounted on plates 144. Screws 150 are adapted to engage extremities on the contact fingers 124a and 124b, in order to move them into or out of engagement with corresponding ones of the contact fingers 6 123m and 123b, and to engage motor contact finger in order to move it relative to the other motor contact finger 125a.

Adjacent to the inner rocker shaft 142, a roller 152 is mounted on a pin 159 carried by an arm 153 which depends from rocker 140, and this roller works in a slot 154 in segment gear 24, which slot provides a cam configuration formed of cam lobes 154a, 154b, and 154C, best seen in FIG. 8. With the parts occupying the positions shown in FIGS. 1 and 2, roller 152 rests upon cam lobe 154a. As will be described, when it is desired to lower stop arm 20, segment gear 24 will be rotated in the direction of the arrow indicated in FIG. 4, that is, counterclockwise. Thus, as soon as segment gear 24 has turned far enough, roller 152 will drop onto cam lobe 154i; and remain thereon for a short period of time. This initial rotary movement of the segment gear will force the rocker to pivot in a clockwise direction, as oriented in FIG. 4, and cause the screws 150 carried on one side thereof to drop away from their associated contact fingers 124b, thereby opening the contacts 1231142412. With roller 152 now occupying a position on the intermediate cam lobe 15412, the contacts 123a-124a still remain open and motor contact 1254250 and back contact 124a-130 remain closed. The continued rotation of segment gear 24, however, forces the roller to move onto lobe 1540, thus increasing the angle through which the rocker travels. In response to this increased angular movement, contact fingers 124a are carried into engagement with their associated contact fingers 123a, back contact 124a130 is opened due to upward movement of the aforementioned one contact finger 124a, and contact finger 125 is carried upwardly out of engagement with contact finger 125a, by means of the contact actuating screws 150 mounted on the opposite side of the rocker. Since contact fingers 125 and 125a are separated from each other, the circuit for motor 73 will be opened and the motor therefore, becomes deenergized. Conversely, upon reverse rotation of segment gear 24, first the contacts 123a124a will open, and back contact 12417- and motor contact 125- 125a will close. When roller 152 returns to the position in which it rests upon cam lobe 154a contacts 123b124b will again close. Thus, when the parts occupy the positions illustrated in the drawings, the fact may be indicated in any suitable manner by circuits established through the contacts 123b-124b. On the other hand, the fact that movement of the trip arm from the operative position to an inoperative position has been completed may be indicated by one of the circuits established through the contacts 123a-124a. Furthermore, the closing of contact 123a-124a concurrent with the opening of back contact 124a130b may be utilized to indicate that movement of trip arm 20 from the inoperative to the operative position has been accomplished in the desired manner, that is, that the circuits through contacts 123a 124a have not been closed accidentally by flood water or by other undesirable effects.

It should be pointed out, however, that since the contact actuating screws are adjustably mounted, by properly adjusting these screws so that their exposed portions are made longer or shorter, the contact fingers 124a and 1241: may be made to cooperate with their associated contact fingers 123a and 124a at different times and thereby provide any desired sequence of contact operation.

Referring now to FIG. 10 and the control circuit illustrated therein, the motor and the winding of brake B- are designated by their reference characters 73 and 86, respectively. The contact fingers which form the safety switch contact 136 138 and the motor contact 125- 125a referred to hereinabove are similarly designated by their respective reference characters. In the preferred embodiment of my invention, motor 73 and brake winding 86 are of the type designed to be operated by alternating current and direct current, respectively. A suitable alternating current source 155 provides the working current and, therefore, a bridge rectifier designated 156 is connected in a conventional manner across winding 86. Also, a typical starting condenser indicated C may be connected across two of the terminals of motor 73. Since rectifier 156 and condenser C may be housed in any convenient compartment provided for them, their diagrammatic showing in FIG. 10 is deemed sufiicient. Current is supplied through contact 125-12511 and 136-138 to the motor 73 and through contact 136-138 and rectifier 156 to brake winding 86 from source 155, over the contacts a and b of an externally operated conventional track relay 162. Relay 162 may be operated, in a manner well known to those skilled in the art, in conjunction with an automatic block signaling system for railroads in which, when it is desired to set the trip arm to the inoperative position, relay 162 may be energized so that the contacts a and b are closed, but that, when it is desired to set the trip arm in the effective position so that it is in a position to actuate the brake system of a passing train, relay 162 may be deenergized so that its contacts a and b open.

I will now assume that with the parts occupying the positions illustrated in the drawings, relay 162 becomes energized. Contacts 11 and b of relay 162 will close to connect motor 73 across the terminals of source 155 over a circuit which includes contacts a and b of relay 162, motor contact 125-12511, and safety switch contact 136- 138. The motor will, therefore, become energized. At the same time, winding 86 of brake B, by means of rectifier 156, will be connected to source 155 over a circuit which includes contacts a and b of relay 162 and safety switch contact 136-138 and the brake will, therefore, also become energized. As a result, armature 96 moves into engagement with pole pieces 87a and 87b, thereby preventing brake shaft 88 and sun gear 91 thereon from rotating. With motor 73 energized, it will turn worm 66 and cause worm gear 64 to revolve, the worm gear through the medium of slip coupling Q and gear carrier 61 in turn causing internal gear 60 to revolve in the direction indicated by the arrow (FIG. 7). Since the planetary gears 56 are interposed betwen the internal gear and sun gear 91, the planetary gears will be caused to travel around and upon the periphery of the sun gear. When this happens, countershaft 48 will rotate pinion 46 causing segment gear 24 to turn, as previously mentioned. This movement of segment gear 24 forces the shaft 14, against the action of springs 40 and 41, to begin to rotate through an angle sufficient to swing the trip arm to a substantially horizontal position. The turning of segment gear 24 pivots the rocker 140 and, as previously described, during movement of roller 152 onto cam lobe 154b shortly after rocker 140 begins to pivot one set of contacts 123b-124b opens. As the trip arm 20 is rotated through a greater angle and reaches its horizontal inoperative position, roller 152 will now rest upon cam lobe 1540 and, by so doing, will close the other set of contacts 12311-12411 substantially simultaneously with opening back contact 12411-1301) and motor contact 125-12511. With the circuit to the motor thus broken, movement of the motor will stop. It will be noted, however, from FIG. 10, that current continues to flow to winding 86. Armature 96 will, therefore, continue to be held against rotation, thereby also preventing sun gear 91 from revolving. At the same time, internal gear 60 will be locked against rotating in the opposite direction due to the above-mentioned self-locking feature of the worm drive. Thus, since internal gear 60 is prevented from being driven backward, and also since sun gear 91 is simultaneously prevented from revolving, trip arm 20 will be held, against the influence of springs 40 and 41, in the inoperative position.

If, however, relay 162 is caused to become deenergized, indicating that the trip arm must occupy the operative position, contacts a and b controlled by relay 162 will release. The breaking of the motor circuit to source 155 which results from the opening of these contacts will in no way affect the operation of motor 73 since, at this time, the motor is already deenergized by the previous opening of motor contact 125-12511. The opening of contacts a and b of relay 162 will, however, open the energizing circuit for winding 86 of the brake. Accordingly, with the circuit to winding 86 interrupted, brake armature 96 and sun gear 91 will be free to rotate. Under these conditions, the springs 40 and 41, whose compression has been increased during the downward movement of trip arm 20, will act upon the parts to cause them to rotate in a reverse order, that is, through the medium of segment gear 24, pinion 46, and countersaft 48, planetary gears 56 will be urged to rotate in a direction opposite to the direction indicated by the arrow in FIG. 7. Since the sun gear is no longer locked against movement, and since internal gear 60 is unable to reverse its direction of rotation, planetary gears 56 will travel about the internal gear while simultaneously traveling around and upon the periphery of sun gear thereby causing the sun gear to spin rapidly about its axis until trip arm 20 abuts against stop 22. The gear carrier 61 is so positioned on main bearing sleeve 52 that slip coupling plate 78 and the gear carrier will slip relative to the worm gear when the trip arm strikes the stop. The energy from the rapidly moving gears is thus diverted from acting upon the worm gear arrangement and is dissipated without causing damage to the teeth thereof. During movement of the trip arm toward its upper position, the cycle of operation of the contacts previously described is performed in a reverse order, as will be appreciated from the drawings.

If, during the movement of the trip arm to its inoperative position, an obstruction occurs which prevents the movement of the trip arm from being completed, the motor 73 may become overloaded and cause slip coupling Q to slip. To prevent damage to the motor in the event the obstruction continues, an overload protection device (not shown), which may be of the thermal type well known in the art, may be connected in the circuit of motor 73 to interrupt the motor circuit in response to a sustained overload, to cause the motor to become energized, and maintain the motor circuit interrupted for a short period of time following which another attempt to move the stop to the horizontal inoperative position can be made.

As can be appreciated from the above, considerable force may be produced by springs 40 and 41 while driving the trip arm toward the effective position, but the arrangement is such that normally the impact between the trip arm and stop is slight. For the purpose, however, of controlling the forceful effect of the springs I provide a paddle wheel 164 (FIG. 6) suitably connected with brake shaft 88 to rotate therewith, and having a pair of vanes 164a and 164b arranged to alternately forcibly pass through the oil bath in the brake compartment during rotation of the brake shaft. Since the vanes will drag in the fluid as the brake shaft revolves during movement of the trip arm toward the effective position, it follows that the effect of the springs will partly be neutralized. Rotation of the brake shaft will, therefore, be retarded and a corresponding amount of retardation to movement of the trip arm will also occur so that a relatively mild impact between the trip arm and stop will result. Obviously, by reducing the susceptibility of these parts to shock, danger of resulting damage thereto by repeated operation of the train stop device is minimized. Also, it will be apparent that the degree of retardation is adjustable partly by varying the size and number of the vanes and partly by controlling the depth and nature of the oil bath.

Attention, however, should be drawn to the fact that while I have shown the paddle wheel providing the movement controlling feature just described, this paddle wheel is not essential and may, if desired, be omitted without impairing the operation and performance of the train stop device as described earlier hereinabove.

Disposed in a central opening 52a in bearing sleeve 52 and abutting against one end of a short plunger 98 whose other end makes firm LJntact with me end of shaft 88 adjacent pin 90, is a coil spring 99 which provides spring pressure urging shaft 88 in a direction toward the right, as oriented in FIG. 6, until the hub of paddle wheel 164 engages bearing 89. By limiting the displacement of the shaft in the direction indicated, and permitting only negligible movement in the opposite direction due to the resiliency of spring 99, the extent of the air gap between armature 96 and the faces of pole pieces 87a and 87b cooperating therewith once established can be accurately maintained.

From the foregoing, it will be apparent that I have provided an electric train stop device which, due to the ready availability of a source of electric power in railroad systems, may be installed inexpensively and maintained at lower cost than other similar prior art devices such as those which rely upon a source of compressed air for power.

Although I have herein shown and described only one form of apparatus embodying my invention, it is understood that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is:

1. Railway traflic controlling apparatus comprising, a rotatable output shaft, an internal gear including a carrier arranged concentrically about a portion of said output shaft and arranged so that said internal gear and output shaft are free to rotate relative to each other, a sun gear encircled by said internal gear and concentric with said output shaft, a planetary gear carried by said output shaft and interposed between said sun gear and internal gear, a brake shaft coupled with said sun gear for carrying it, brake means for braking said brake shaft or not according as said brake means is or is not applied thereto, an electric motor, a gear train with one end thereof connected in operative relation with said motor but incapable of transmitting motion thereto, the other end of said gear train being connected to said carrier in driving relation whereby when said motor is energized and said brake means is applied movement of said motor is transmitted through said gear train and carried to said internal gear to revolvably drive said planetary gear about said sun gear in one direction, resilient means for opposing movement of said planetary gear in said one direction, and control means actuated in response to a predetermined amount of movement of said planetary gear in the one direction for deenergizing said motor concurrent with maintaining said brake means applied.

2. Railway traflic controlling apparatus comprising, a rotatable shaft, an internal gear including a carrier arranged in rotative relation thereto, a worm gear arranged concentrically about said carrier and arranged in driving relation therewith, a nonreversible worm meshing with said worm gear, an electric motor connected with said worm to drive it, a sun gear encircled by said internal gear and concentric with said shaft, a planetary gear carried by said shaft in mesh with said sun gear and internal gear, a brake shaft coupled with said sun gear, an electromagnet including a magnetizable armature rotatable with and slidably mounted on said brake shaft whereby said brake shaft is or is not held against rotation according as said electromagnet is or is not energized, control means for connecting said motor and electromagnet with energizing circuits whereby when said motor and electromagnet are concurrently energized said sun gear constitutes a track about which said planetary gear is revolvably driven in one direction by said internal gear, resilient means operatively connected with said planetary gear for opposing movement thereof in the one direction, and other control means for disconnecting said motor from the energizing circuit thereof at the end of a predetermined period of time but maintaining said electromagnet connected with the energizing circuit thereof.

3. Railway traffic controlling apparatus comprising a nonreversible worm, an energizable power device con nected with said worm for driving it, a bearing sleeve normal to the longitudinal axis of said worm, an internally disposed output shaft extending beyond the ends of said sleeve and being journaled therein, an internal gear including a carrier mounted concentrically on the periphery of said sleeve to allow relative rotation of said internal gear and output shaft, a Worm gear mounted concentrically on said carrier and in mesh with said worm, slip coupling means arranged concentrically about and rotatable with said carrier for holding said worm gear and internal gear in driving relation with one another, a planetary gear carried by said output shaft in mesh with said internal gear, a sun gear in mesh with said planetary gear, resilient means operatively connected to said planetary gear for opposing its movement relative to said sun gear in one direction, a journaled brake shaft coupled with said sun gear for carrying it, an electromagnet arranged to resist rotation of said brake shaft when said electromagnet is energized, parallel energizing circuits for said power device and electromagnet, control means for connecting said power device and electromagnet to their respective circuits thereby effecting movement of said planetary gear about said sun gear in said one direction, and means responsive to motion of said planetary gear in said one direction for disconnecting said power device from the energizing circuit thereof following a predetermined amount of movement of said planetary gear.

4. In combination, railway traffic controlling apparatus comprising a housing, an output shaft journaled in said housing, a trackway trip arm operatively connected with said output shaft, a planetary gear carried by said output shaft, an internal gear in mesh with said planetary gear and including a carrier arranged concentrically about a portion of said output shaft and arranged in rotative relation thereto, a worm gear arranged concentrically about said carrier and held in driving relation with said carrier by means of a slip coupling, a nonreversible worm in mesh with said worm gear, an electric motor connected with said worm to drive it, a sun gear in mesh with said planetary gear, an electromagnet including a brake shaft connected with said sun gear for carrying it, means controlled by said electromagnet for holding said brake shaft against rotation when said electromagnet is energized, parallel energizing circuits for said motor and electromagnet including a switch in common with said circuits, said planetary gear being driven in one direction about said sun gear by said internal gear when said switch is closed to transmit motion from said motor and through said output shaft to move said trip arm, means effective during said movement of said trip arm for disconnecting said motor from the energizing circuit thereof at the end of a period of time sufiicient to move said trip arm to an ineffective position, and resilient means responsive to movement of said motor for moving said trip arm to an effective position when said switch is opened.

5. In combination, railway traflic controlling apparatus comprising a housing, an output shaft journaled in said housing, a trackway trip arm operatively connected with said output shaft and movable therewith between effective and ineffective positions, a planetary gear carried by said output shaft, an internal gear meshing with said planetary gear and including a carrier arranged concentrically about a portion of said output shaft and arranged in rotative relation thereto, a worm gear journaled on said carrier and arranged in driving relation therewith, a nonreversible worm in mesh with said worm gear, an electric motor arranged to operate said worm, a sun gear in mesh with said planetary gear, an electromagnet including shaft means connected with said sun gear for carrying it, means controlled by said electromagnet when it is energized for holding said shaft means against rotation whereby rotation of said sun gear is simultaneously resisted, parallel energizing circuits for said motor and electromagnet including a switch in common with said circuits, said planetary gear being driven about said sun gear by said internal gear when said switch is closed to transmit motion from said motor to said output shaft and swing said trip arm from an effective to an ineffective position, means connected in the energizing circuit of said motor and operated in response to motion thereof for terminating the energization of said motor substantially when movement of said tn'p arm to an ineffective position is completed, said electromagnet being maintained energized over a circuit including said switch when said motor is at rest and said switch is closed, and resilient means effective when said switch is opened and said motor remains at rest for returning said trip arm to an effective position.

6. In combination, railway traflic controlling apparatus comprising a housing formed with a compartment of lubrication fluid, a shaft rotatably supported over said fluid and having a portion extending outwardly of said compartment, a trackway trip arm operatively connected with said shaft outside said compartment, resilient means for biasing said trip arm to an effective position, a planetary gear carrier by said shaft inside said compartment, an internal gear in mesh with said planetary gear and including a carrier arranged concentrically about a portion of said shaft and arranged so that said internal gear and shaft are free to rotate relative to each other, a rotatably supported sun gear in mesh with said planetary gear, actuable brake means operably connected with said sun gear for resisting rotation thereof when actuated, energizable unidirectional power means drivably connected with said carrier for, when said brake means and power means are actuated and energized respectively, revolving said shaft through said internal gear and planetary gear in a direction to swing said trip arm from an effective position to an ineffective position, circuit means for automatically terminating the energization of said power means when said trip arm reaches an ineffective position, controllable means for thereafter causing said brake means to become deactuated to enable rotation of said sun gear and the return of said trip arm to an effective position, and means rotatable with said sun gear and dragging in said fluid for retarding rotation of said sun gear and correspondingly decelerating the swinging motion of said trip arm to an effective position.

7. In combination, railway traffic controlling apparatus comprising a housing formed with a compartment of lubrication fluid, a shaft rotatably supported over said fluid and having a portion extending outwardly of said compartment, a trackway trip arm operatively connected with said shaft outside said compartment, resilient means for biasing said trip arm to an effective position, a planetary gear carried by said shaft inside said compartment, an internal gear in mesh with said planetary gear and including a carrier arranged concentrically about a portion of said shaft and arranged so that said internal gear and shaft are free to rotate relative to each other, a rotatably supported sun gear in mesh with said planetary gear, actuable brake means operably connected with said sun gear for resisting rotation thereof when actuated, nected with said carrier for, when said brake means and power means are actuated and energized respectively, revolving said shaft through said internal gear and planetary gear in a direction to swing said trip arm from an effective position to an ineffective position, means for automatically terminating the energization of said power means when said trip arm reaches an ineffective position, controllable means for thereafter causing said brake means to become deactuated to enable rotation of said sun gear and the return of said trip arm to an effective position, and a paddle wheel operably connected with said sun gear for rotation therewith and including at least one vane arranged to drag in said fluid as rotation of said sun gear occurs, the operation of the apparatus being such that, during the return of said trip arm to an effective position, the resistance to movement of the vane caused by the fluid will partly neutralize the influence of said resilient means whereby the speed of said trip arm is controlled during movement of said trip arm toward the effective position thereof.

References Cited by the Examiner UNITED STATES PATENTS 1,116,316 11/14 Mischansky 246-191 1,272,099 7/ 18 Rekers 246244 1,297,969 3/ 19 Rekers 246-244 1,881,516 10/32 Griswold 246244 2,183,164 12/39 McWhirter et a1. 246-242 2,301,168 11/42 Frantz 74-781 2,388,819 11/45 Bone 246242 2,500,447 3 /50 Bitzer 74781 2,566,945 9/51 Laze 74785 2,984,126 5/61 Feaster 74-781 DON A. WAITE, Primary Examiner.

BROUGHTON G. DURHAM, LEO J. LEONNIG,

Examiners.

UNITED S:1ATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,211,017 October 12, 1965 Rankin J. Bush It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column.1l, line 25, for "carrier" read carried column 12, line 12, after "actuated," insert energizabl-e unidirectional power means dr'ivably con- Signed and sealed this 15th day of February 1966.

SEAL) Lttest: ERNEST w. SWIDER EDWARD J. BRENNER Ltteating Officer of Patents 

1. RAILWAY TRAFFIC CONTROLLING APPARATUS COMPRISING, A ROTATABLE OUTPUT SHAFT, AN INTERNAL GEAR INCLUDING A CARRIER ARRANGED CONCENTRICALLY ABOUT A PORTION OF SAID OUTPUT SHAFT AND ARRANGED SO THAT SAID INTERNAL GEAR AND OUTPUT SHAFT ARE FREE TO ROTATE RELATIVE TO EACH OTHER, A SUN GEAR ENCIRCLED BY SAID INTERNAL GEAR AND CONCENTRIC WITH SAID OUTPUT SHAFT, A PLANETARY GEAR CARRIED BY SAID OUTPUT SHAFT AND INTERPOSED BETWEEN SAID SUN GEAR AND INTERNAL GEAR, A BRAKE SHAFT COUPLED WITH SAID SUN GEAR FOR CARRYING IT, BRAKE MEANS FOR BRAKING SAID BRAKE SHAFT OR NOT ACCORDING AS SAID BRAKE MEANS IS OR IS NOT APPLIED THERETO, AN ELECTRIC MOTOR, A GEAR TRAIN WITH ONE END THEREOF CONNECTED IN OPERATIVE RELATION WITH SAID MOTOR BUT INCAPABLE OF TRANSMITTING MOTION THERETO, THE OTHER END OF SAID GEAR TRAIN BEING CONNECTED TO SAID CARRIER IN DRIVING RELATION WHEREBY WHEN SAID MOTOR IS ENERGIZED AND SAID BRAKE MEANS IS APPLIED MOVEMENT OF SAID MOTOR IS TRANSMITTED THROUGH SAID GEAR TRAIN AND CARRIED TO SAID INTERNAL GEAR 